1. 使用OkHttp进行HTTP请求：

OkHttpClient client = new OkHttpClient.Builder()
        .authenticator(new TokenAuthenticator())//设置令牌认证器
        .build();

Request request = new Request.Builder()
        .url(url)
        .build();

Response response = client.newCall(request).execute();

2. 设置令牌认证器(Token Authenticator):

private class TokenAuthenticator implements Authenticator {
    @Override
    public Request authenticate(Route route, Response response) throws IOException {
        if (response.code() == 401) {//判断HTTP响应码是否为未授权
            String token = refreshToken();//刷新令牌
            return response.request().newBuilder()
                    .header("Authorization", "Bearer "+token) //添加刷新后的令牌
                    .build();
        }
        return null;//未出现HTTP 401时，返回null
    }
}

3. 刷新令牌方法:

private String refreshToken() throws IOException {

    OkHttpClient client = new OkHttpClient();

    RequestBody requestBody = new FormBody.Builder()
            .add("grant_type", "refresh_token")//设置刷新参数
            .add("refresh_token", "your_refresh_token_here")//添加授权码
            .build();
    
    Request request = new Request.Builder()
            .url("http://your_oauth_server_url_here")
            .post(requestBody)//使用POST请求
            .build();

    Response response = client.newCall(request).execute();

    if (!response.isSuccessful())
        throw new IOException("Unexpected code " + response);

    String responseBody = response.body().string();

    JSONObject json = new JSONObject(responseBody);
    String newToken = json.getString("access_token");

    return newToken;
}